The aim of this project is to study the causal relationship between developmental changes in achievement-related motives, beliefs, attitudes, and behaviors, and systematic changes in social environments. Early adolescence is a critical period for the development and consolidation of attitudes toward the self, values, and aspirations which impact significantly on mental health and behavior throughout the life span. Yet this period is characterized by a surge in behavioral disturbances and a decline in achievement motivation. We hypothesize that modifiable classroom processes at the junior high school level precipitate the decline in self-concept of ability, the valuing of academic subjects, expectations for success, intrinsic motivation, mastery orientation, and continuing motivation, which, in turn, mediate changes in other social and academic behaviors. Using a longitudinal, quasi-experimental design, we will assess children's achievement-related attitudes in contrasting classsroom environments at four points during the critical transition from elementary school to junior high school. To test for the effect of control and choice, we will contrast students moving into a traditional science program with students moving into a non-traditional program in which students are given some control over procedures and academic work. The effect of heightened social comparison will be tested in three ways: 1) students moving into a math program in which grades are based on relative performance will be contrasted with students moving into a math program in which grades are based on completing contracted work, 2) students moving into math classes in which students are grouped homogeneously by ability will be contrasted with students moving into math classes in which students are heterogeneous in ability, and 3) the attitudes of students moving into a subject area using a public drill format with public evaluative feedback (math classes) will be contrasted with their attitudes as they move into a subject area using less public drill and evaluation (English classes). To assess whether the changes we observe are age- or grade-related, we will include a control sample of children who move into a traditionally structured junior high school program at the 6th rather than at the 7th grade. Interviews and questionnaires will be used with students and teachers. Classroom measures will be used to assess student, teacher, and observer perceptions of environment. Test scores and grades from students' records will be collected annually.